When the gateway receives SIGTERM/SIGINT, the shutdown handler now
runs 'ps aux' and logs every hermes/gateway-related process (excluding
itself). This will show in agent.log as:
WARNING: Shutdown diagnostic — other hermes processes running:
hermes 1234 ... hermes update --gateway
hermes 5678 ... hermes gateway restart
This is the missing diagnostic for #5646 / #6666 — we can prove
the restarts are from systemctl but can't determine WHO issues the
systemctl command. Next time it happens, the agent.log will contain
the evidence (the process that sent the signal or called systemctl
should still be alive when the handler fires).
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